Rheostat



E. M. SORENG July 24, 1934.

Filed March 11, 1931 2 Sheets-Sheet l R W w W Edgar M. Sub/mg A TTOPNE) July 24, 1934. W E M, SQRENG 1,967,519

RHEOS'IAT Filed March 11, 1931 2 Sheets-Sheet 2 INVEN TOR B) wan/Wu ATTORNEY Patented m 24, 1934 1,967,519

, UNITED STATES PATENT. OFFICE 1,967,519 nrmosm'r Edgar M. Soreng, Chicago, 111., assignor to So reng-Manegold Company, Chicago, 111., a corporation of Illinois Application March 11, 1931, serial No. 521,681

6 Claims. (01. 2oo 1 1) This invention relates to certain new and use- Figure 7 is a rear view of the switch structure ful improvements in rheostatsand hasas an shown inFigure 6; object to provide a small and compact rheostat Figure 8 is a perspective view of thehousing having a switch incorporated therein and parfor the structure shown in Figure 6; ticularly adaptable to control the flow of cur- Figure 9 is a perspective view of the movable 0 rent to, and the speed of, an electrical transcontactor; lating device such as the fan motor of a hot Figure 10 s B P p t ve V w O t mou water automobile heater. It is, however, undering head; and stood that the device may be used for other ur 1 is a p sp tive vi w of the various in kindred purposes and is exceptionally well suited elements f the driver shown ep rated and in for use as a dimming switch. their op o der of assembl A more specific object of this invention re- Referring now more pa u a y o the ee-' sides in the novel manner of imparting motion panying drawings in w c li e nu erals to the movable element of the crheostat and in designate like parts u out the Several 16 the means for providing a detent action to posiws, th num al 6 r pres nts a substan ia tively indicate the various positions of the mov- D Shaped hou easing d a 1'0m able element. stamping material and having a bottom wall 7 And a further object of this invention is to and an a ular S de wall 8. provide a rheostat device of the character deecu d o the bo om wa '1 is a ubula 2o scribed which, dueto its extremely simple conexternally eaded stem 9 w extends struction and minimum number of ts, i i wardly from the casing and provides means for expensive and lends itself particularly well to m un the rh stat f m a pan 0,as il usproduction methods of manufacture. v tratedlin Figure e mounting tem 9 is with the above and other objects in view pass d hr u a su a ap u in th p n l 25 which will appear as the description proceeds, is u d thereon by u The u s 11 so my invention resides in the novel construction, also serve to hold a dial 12 a a t the f ont of combination and arrangement of parts substanthe Panel, which bears indieia representing the tially as hereinafter described and more particu- Various {functions Operative "Conditions Of e larly defined by the app nd d cl i it being rheostat, andrelative rotation between the dial 30 understood that such changes in the precise 12 and the mounting Stem 9 is Prevented y a embodiment of the hereindisclosed invention P j ti n 3 xt nd d f the d p n may be made as come ithi t scope of t into a longitudinal slot 14 in the outer end of claims. the mounting stem, see Figure 1.

In'the accompanying drawings, I have ill s- Journaled in the mounting stem is a shaft 15,

35' trated one complete example of the physical the Outer end of which D i the Stem embodiment of my invention constructed acto mount an actuating knob 16 and the inner cording to the best mode I have so far devised end Projects into e easing and has a p for the practical application of the principles like driver non-rotatablv secured thereto, as thereof, and in which; l at 18. The driver 17 has a non-rotatable con- 40 Figure 1 is a front elevation of a rheostat 'neetion w a m v l contact r y l embodying my invention ith a portion of t ment, indicated generally by the numeral 19 and dial broken away; rotatably carried by a mounting head 20 of Figure 2 is a longitudinal sectional view insulating material w c closes the o side of through the rheostat illustrating the manner of h casing and is d as e b d t th y 45 mounting the me from panel; tangs 21 projected from the annular casing wall Figure 3 is a rear l v ti with a portion of 8 and struck over the outer face of the mountthe mounting head broken away to illustrate r dstructural details; v The movable contact carrying element com- Figure 4 is a perspective view of the. housing prises a diametrically extending strip 22 of 60 or casing; and spring-metal rotatably mounted on the panel Figure 5 is a perspective view of th t- 20 by a rivet or other suitable pivot means 23 ing head and the movable elements carried which extends through e Panel d 80 thereby shown detached from the casing; mounts a terminal 24, the terminal being elec- Figure dis a view similar to Figure 2 of a. t ica y connected w th t e meta str p t ou h 65 slightly modified form of my invention; the rivet. Disposed between the strip 22 and the inner face of the mounting panel is a washer 25 and at one side of its point of pivot the strip 22 has a protrusion 26 struck therefrom which engages the adjacent face of the washer 25 and rides thereon as the strip is rotated about the axis of its mounting. I

At its end, opposite the protrusion 26, the strip 22 carries a movable contactor 27 which, together with the protrusion 26, causes the strip 22 to bow and yieldably urge the movable contactor toward the mounting head for selective engagement with a plurality of stationary contacts 28 carried by the head 20. The stationary contacts 28 are icupped to cooperate with the movable contactor and provide a detent action, and have portions 29 projected from the outer face of the mounting head to which the ends of a series of resistance coils 30 are electrically and-mechanically connected. The series of coils are preferably formed of one continuous length of wire and their adjacent attaching ends 31 are provided by extended loops. The extreme end 32 of one of the outer coils is secured to one of the stationary contacts through a terminal 33 which is secured to the mounting head by the adjacent stationary contact.

The movable contactor 27 being electrically connected with the terminal 24 through the metal strip 22 and being selectively engageable with the stationary contacts, it is readily apparent that, upon movement of the movable contactor, any one or all of the resistance coils may be connected in series with external conductors, not shown, connected to the terminals 24 and 32, or when the movable contactor is engaged with the stationary contact to which the terminal 33 is electrically connected, all of the resistance coils are shunted out of the circuit. In the present instance the movable contactor has five positions, and as there are but four stationary contacts, it follows that when the movable contactor is in its extreme position opposite that at which it is electrically connected with the terminal 33, it merely engages the inner surface of the mounting head and thus breaks the continuity of the circuit across the terminals 24 and 33 so that also serves as a switch.

The manner of imparting motion from the ating material, which is provided with diametri-.

cally opposite recesses or openings 35. The driver 17, as best illustrated in Figure 4, comprises a pair of diametrically extending arms-36 and 3'7 arranged at substantially right angles to each other and the outer ends of the arm 37' are directed laterally, as at 38, and have tangs or projections 39 at their extreme ends which are engageable in the recesses 35 of the ring 34 forming part of the movable contactor assembly. Rotation is thus imparted from the driver to the movable contactor.

To provide a positive and effective indication 'of the various positions of the rheostat, the detent action obtained through the cooperation of the movable contactor with the stationary contacts is augmented by a novel detent action afiorded by ball bearings or other similar elements 40 mounted in apertures 41 at the' extremities of the driver arm 37 and engageable in depressions 42 formed in the casing wall 7. The depressions 42 are circumferentially spaced pointer.

the rheostat' mergers at proper intervals to releasably hold the driver -in its respective positions maintaining the movable contactor properly engaged with any one stationary contactor in its circuit breaking posithe driver-arm 36 so that a yielding pressure is maintained on the ball bearings.

To limit the motion of the driver, a tang 43 is struck inwardly from the casing wall 3 to lie in the path of the ends of the driver arm 36, see Figure 3.- A

' In Figures 6 to 11 inclusive, a slightly modified.

embodiment of this invention is shown. In this construction, as in the embodiment described, the casing or housing 6 is supported from a .panel 10 by a tubula stem 9, and the switch mechanism within the housing is actuated by means of a shaft 15 journalled in the stem and having an actuator 16' of slightly different construction on its outer end. A dial 12 is also provided, but in place 'of the pointer on the meV actuator, a knurled screw 44 which secures the actuator on the shaft andprojects radially from the actuator, performs the function of the The switch mechanism within the housing consists of the same general elements, but their construction is different than that shown in Figures 1 to 5 inclusive. The driver particularly is of different construction, and consists of an elongated metal strip 45, a spring strip 46 of ,the strips 45 and 46 and the clip 48 receive by the arms of the clip 47. The outer ends of the clip 4'7 are engaged in suitable recesses 50 formed in a plate of insulating material 51 riveted or otherwise attached to the medial portion 52 of the movable contactor and as best illustrated in Figure 4 themedial portion of the movable contactor conforms generally to the size and shape of the plate 51. The opposite ends 53 of the contactorare offset to lie in a plane outwardly of "the medial portion 52 and form contacts which are engageable with stationary contacts 54 carried by the mounting head 20.

It is noted that the movable contactor is not mounted from the head 20, but is supported entirely by the engagement of the arms of the clip 47 in the recesses 50, and to hold the contactor against the head 20 and provide the necessary contact pressure, an expansive spring 55 is confined between the insulating plate 51 of the movable contactor and the clip 48, the arms or flanges of the clip 48 cooperating with the arms of the clip 47 to provide a pocket in disposed on the inner surface of the mounting 50 head and the resistance coils on the outside surface. The resistance coils are so located that upon movement of the contactor from its off position to its first circuit making position, all of the resistance coils are in series with the two terminals 58 mounted on the front of the mounting head, and as the movement of the contactor is continued, the resistance coils are shunted out of the circuit. I

The detent action for indicating the various positions of the switch is afforded by balls 59 received in openings 60 in the extremities of the metal strip 45 to be guided thereby formovement with the driver andheld against the closed walrof the housing by the spring strip 46. As in the embodiment shown in Figures 1 to 5 inclusive the balls enter depressions 42 in the closed wall of the housing to indicate the various positions of the switch.

From the foregoing description taken in connection with the accompanyingdrawings, it will be readily apparent to those skilled in the art to which an invention of the character described appertains, that I provide a novel rheostat and switch, which is particularly adapted to regulate the speed of hot water vehicle motors, and in which a positive detent action is obtained in a simple and effective manner. It will also be apparent that rheostats constructed in accordance with this invention, due to their simplicity and minimum number of parts, lend themselves especially well to production or manufacture.

What I claim as my invention is:

1.- In a device of the character described, a casing, a movable switch element within said casing, a. tubular mounting stem for the casing, a movable switch driver within the casing adapted to actuate said switch element, means journaled in said mounting stem and rotatably mounting the driver within the casing, oppositely extending arms on said driver, cooperating means carried by the extremities of one arm and the casing providing a detent action to indicate difierent positions of the driver, and means carried at the extremities of the other arm for imparting the motion of the driver to said movable switch element. r

2. In ajdevice of the character described, a casing, a movable contactor assembly within the casing, a driver, an actuating stem rotatable with respect to the casing and mounting'the driver within the casing, said driver having a diametrically extending arm formed of resilient metal, ball elements rotatable between the extremities of said arm and one wall of the casing and engageable in depressions in said casing wall to provide a detent action to indicate the various positions of the driver, the medial portion of said diametrically extending arm being.

adjacent said casing wall whereby the arm is bowed to, maintain a yielding pressure on the ball means.

3. In a device of the character described, a casing, a movable switch element within the casing, a driver within the casing for imparting rotation to the movable switch element, and means providing a detent action to indicate the position of'the driver and movable switch element comprising, radially extending spring arms movable with the driver, and ball members engaging openings at the extremities of the raa terminal for the movable contactor on the exterior face of the terminal head, common means to mount said terminal on the terminal head and pivotally mount the strip of spring metal on the inner face of the terminal head and electrically connect the terminal with said strip of spring metal, said movable contactor being of such size as to how the strip of spring metal, whereby the inherent resiliency of said strip provides contact pressure, a di-electric member attached to the strip of spring metal, and an actuator drivingly' engaging said di-electric member within the casing to impart movement to said strip to carry the movable contactor from one stationary contact to the other.

5. In an electric switch device of the character described, a cup-shaped casing, an actuator shaft rotatably mounted from saidcasing, a contactor driver attached to the shaft within the casing and comprising, a plurality of radially extending arms, the extremities of two opposite arms having ball retaining means, ball members disposed in said ball retaining means and engagingthe adjacent inner face of the casing wall, said ball members being of a size to cause said radially extending arms to bow, whereby the inherent resiliency of said arms urges the ball members toward the casing wall, depressions in said casing wall in which said ball members are engageable to afford detent means and define various predetermined positions of said driver, and a movable contactor assembly operable from said driver.

6. In an electric switch device of the character described, a casing, a di-electric'terminal head providing a cover for the casing, a plurality of stationary contacts on the terminal head, a movable contactor to be selectively engaged with said stationary contacts, means to permanently movably mount said movable con tactor, on the terminal head and to provide spri g tension to afford contact pressure whereby said movable contactor, its mounting and the di-electric terminal head comprise" a unit, an actuator shaft carried by the casing, a driver for the movable contactor within the casing attached to the actuator, shaft and held assembled thereby with the casing, cooperating means carried by the, driver and the casing to aiford a detent action, whereby the casing, the

actuator shaft, the driver and the detent means.

form a unit independent of said other unit, and means to provide a driving connection between said driver and the movable contactor assembly upon attachment of the di-electric terminal head to the casing.

- EDGAR M. SORENG. 

